Anthropometry Of Deep-Set Eyes With Respect To Difficulty In Docking During Femtosecond Laser

To identify the facial anthropometric parameters that predict the difficulty in docking during femtosecond laser. 

A single centre observational study conducted on participants who were planned for FS- LASIK or SMILE at Dr. R. P Centre for Ophthalmic Sciences.

The front and side facing images of the participants were analyzed using Image J software to measure different anthropometric parameters. Nasal bridge index, facial convexity and other parameters were measured. The difficulty faced by surgeon during docking was recorded for each subject. The data was analyzed on Stata 14.2.

A total of 97 subjects were included. The mean age was 24 (+ 7) years. 23 (23.71%) subjects were females while the rest were males. Difficulty in docking was seen in 1 (4.34%) female and 14 (19%) males. The mean nasal bridge index was 92.58 (+ 4.01) in subjects with deep set eyes and 89.72 (+ 4.30) in normal subjects. Mean total facial convexity was 129.28 (+ 4.24) in deep set eyes, and 140.23 (+ 4.74) in normal subjects.

Total facial convexity was the most important factor, with the value being less than 133 degrees in most subjects with unfavorable facial anthropometry. We thus describe a feasible tool to predict the difficulty during docking, which may help improve the surgical experience for novice surgeons.